26 



BULLETIN" 183, U. S. DEPARTMENT OF AGEICULTUBE. 



grain the protoi^lasm of the cells of the embryo is active and possessed 

 of all the vitality of newly formed tissue, yet barley germinates very 

 imperfectly at this time. Tlie epithelial layer will attack the endo- 

 sperm, even under the most favorable conditions of moisture, tem- 

 perature, etc., only in a weak, erratic manner. The cells do not seem 

 ready to exert their full force. In fact, it is only after a certain 

 period of rest that the grain displays its full germinative potency and 



becomes thoroughly re- 

 teponsivc to germinative 

 influences. 



It has been noticed 

 that the "sweating" 

 process in the curing of 

 barley is closely con- 

 nected with this change 

 in the internal energy of 

 the grain. If grain be 

 sweated in the stack, 

 both the percentage and 

 the vigor of its germina- 

 tion are increased to the 

 maximum. Any other 

 method of treatment 

 after cutting is inferior, 

 the changes being 

 brought about under 

 more adverse conditions. 

 If the curing jDrocess 

 takes place in the shock, 

 it occurs irregularly and 

 imperfectly and at the 

 same time the grain is 

 exposed to the weather. 

 If it occurs in the bin, 

 there is danger of over- 

 heating and consequent 

 damage. The vigor of germination may be affected in this way even 

 when there is no visible indication that deterioration has occurred. 

 Of course the injury is likely to be more serious and even to make 

 the use of the barley for malting purposes impossible. 



These various factors of efficiency m the conversion of the barley 

 grain, when applied to commercial malting operations, presuppose 

 pedigreed barley. The efficiency of the ordinary market barley may 

 be increased by careful culture, but it will never become really supe- 

 rior. The commercial varieties as they are sold in the markets are 

 composed of many subvarieties (fig. 7). The Manchuria, the Oder- 



FiG. 7. — Two grains of barley from a commercial sample, showing 

 the extremes of variation to be found in barleys as grown at 

 present in this country. Economical malting of abarley that 

 contains any considerable percentage of such extreme shapes 

 is impossible. 



